Loan Calculator
Enter a loan amount, term and interest rate to see your monthly payment, total interest and the full cost of the loan.
Example
A $25,000 loan at 7.5% over 5 years costs about $501/mo. You'd pay roughly $30,054 in total — about $5,054 of that is interest.
How it works
Monthly payment uses the amortization formula M = P · r / (1 − (1 + r)−n), where P is the principal, r is the monthly interest rate and n is the number of monthly payments. Total interest is simply the sum of all payments minus the principal.
Good to know
This loan calculator turns three numbers — the amount you borrow, the interest rate, and the repayment term — into the figures that actually matter when you sign: your fixed monthly payment, the total interest you'll pay over the life of the loan, and the grand total you'll hand back to the lender. It's built for anyone weighing a fixed-rate, fully-amortizing loan, such as an auto loan, an unsecured personal loan, or a student loan, where the rate and payment stay the same every month.
Reach for it when you're comparing offers or shaping a borrowing decision: shop the same amount and term across a few quoted rates, or test how stretching the term changes the monthly payment versus the lifetime cost. Because it runs entirely in your browser, you can plug in real rate quotes without any account or data leaving your device.
To read the output, look past the monthly payment alone. The two cost figures tell the real story: total interest is the price you pay for borrowing, and total paid is principal plus that interest combined. A longer term shrinks the monthly payment but usually raises total interest, while a shorter term does the reverse, so the same loan can look "cheap" or "expensive" depending on which number you focus on.
One practical caveat: the result assumes a constant rate and a standard payment schedule, so it won't capture origination fees, insurance, taxes, or a variable rate, and it doesn't model extra principal payments. If you plan to pay ahead, your real interest will be lower than shown — a rough way to gauge the benefit is to re-run the math with a shorter term and compare the total interest.
Frequently asked questions
What kinds of loans does this work for?
Any fixed-rate, fully-amortizing loan — auto loans, personal loans, student loans and more. Enter the term in years or months.
What's the difference between total paid and interest?
Total paid is every monthly payment added together; interest is that total minus the original loan amount — the true cost of borrowing.
Can I model extra payments?
This calculator models the standard schedule. Extra principal payments reduce total interest, but aren't modeled here — lower the term to approximate the effect.
Is my data uploaded anywhere?
No. Everything is calculated in your browser with JavaScript — nothing is sent to a server, so it's private and works offline once loaded.
Is this calculator free?
Yes, completely free with no sign-up and no limits.
People also ask
How is a loan monthly payment calculated?
It uses the amortization formula M = P · r / (1 − (1 + r)^−n), where P is the loan principal, r is the monthly interest rate (annual rate divided by 12), and n is the total number of monthly payments. The result is a level payment that covers both interest and principal each month.
Does a lower interest rate or a shorter term save more money?
Both reduce total interest, but in different ways. A lower rate cuts the cost of borrowing at every payment, while a shorter term reduces how long interest accrues but raises the monthly payment; comparing the total-interest figure for each scenario shows the trade-off.
What is the difference between APR and interest rate on a loan?
The interest rate is the cost of borrowing the principal, while APR also folds in certain fees like origination charges, expressed as a yearly percentage. This calculator uses the stated interest rate, so a loan's true APR may be higher once fees are included.
Why does most of my early payment go to interest?
In an amortizing loan, interest is charged on the remaining balance, which is highest at the start. So early payments are mostly interest and little principal, and the mix gradually shifts toward principal as the balance falls.
How much does loan term length affect total interest?
Lengthening the term lowers each monthly payment but means interest accrues over more months, which typically increases the total interest paid. Shortening the term has the opposite effect: higher monthly payments but less interest overall.
Can I use this for a mortgage?
It works for any fixed-rate, fully-amortizing loan, so the core payment math is the same as a mortgage. However, it doesn't account for property taxes, homeowners insurance, or PMI, so a dedicated mortgage calculator is better for total housing costs.
Does paying off a loan early reduce the interest shown here?
Yes. Making extra principal payments lowers the balance faster, so less interest accrues than the standard schedule shown here. This tool models only the regular schedule, so actual interest with early payoff would be lower.
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